
<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8" />
    <style>
        * {
            margin: 0;
            padding: 0;
            overflow: hidden;
        }

        body,
        #box {
            width: 100%;
            height: 100vh;
        }
    </style>
</head>

<body>
    <div id="box"></div>
    <script type="importmap">
        {
            "imports": {
                "three": "./three/build/three.module.js",
                "three/addons/": "./three/examples/jsm/"
            }
        }
    </script>
    <script src="./tween.umd.js"></script>


    <script type="module">
        import * as THREE from 'three'
        import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
        import { GLTFLoader } from 'three/addons/loaders/GLTFLoader.js'
        import { DRACOLoader } from 'three/addons/loaders/DRACOLoader.js'

        const box = document.getElementById('box')
        const scene = new THREE.Scene()

        const camera = new THREE.PerspectiveCamera();  //相机
        camera.position.set(100, 200, 200); //相机位置
        camera.lookAt(150, 0, 10); //相机位置
        const renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true, logarithmicDepthBuffer: true })
        scene.add(new THREE.AmbientLight(0xffffff, 1))
        scene.add(new THREE.AxesHelper(1000))

        // --------------------renderer启用阴影--------------------
        renderer.shadowMap.enabled = true; // 启用阴影映射
        renderer.shadowMap.type = THREE.PCFSoftShadowMap; // 使用软阴影
        // --------------------renderer启用阴影--------------------

        // --------------------平行光开始--------------------
        // 创建一个平行光
        const directionalLight = new THREE.DirectionalLight(0xffffff, 5);
        directionalLight.position.set(500, 300, 500).normalize(); // 设置平行光的方向
        directionalLight.castShadow = true; // 启用平行光的阴影
        // 配置平行光的阴影贴图
        directionalLight.shadow.mapSize.width = 1024; // 阴影贴图的宽度
        directionalLight.shadow.mapSize.height = 1024; // 阴影贴图的高度
        directionalLight.shadow.camera.near = 0.5; // 阴影摄像机的近裁剪面
        directionalLight.shadow.camera.far = 5000; // 阴影摄像机的远裁剪面
        directionalLight.shadow.camera.left = -500;
        directionalLight.shadow.camera.right = 500;
        directionalLight.shadow.camera.top = 500;
        directionalLight.shadow.camera.bottom = -500;

        directionalLight.position.set(200 * 2, 500 * 2, 200 * 2);
        // 将平行光添加到场景中
        scene.add(directionalLight);
        // --------------------平行光结束--------------------


        // --------------------地面开始--------------------
        const planeGeometry = new THREE.PlaneGeometry(500, 500);
        const planeMaterial = new THREE.MeshStandardMaterial({ color: 0x808080, side: THREE.DoubleSide });
        const plane = new THREE.Mesh(planeGeometry, planeMaterial);
        plane.receiveShadow = true; // 启用接收阴影
        plane.rotation.x = -Math.PI / 2; // 使平面水平
        scene.add(plane);
        // --------------------地面结束--------------------

        // 加载模型 gltf/ glb 
        const loader = new GLTFLoader()
        loader.load('./zhanji.glb', (gltf) => {
            scene.add(gltf.scene)
            gltf.scene.scale.set(0.005, 0.005, 0.005)

            //绕x轴旋转π/4
            gltf.scene.rotateY(Math.PI / 4);

            //创建一段平移的动画
            const tween = new TWEEN.Tween(gltf.scene.position);
            tween.to({ x: 100, y: 50, z: 100 }, 5000).onComplete(function (obj) {

                // 跳转方向，连续动画
                gltf.scene.rotateY(Math.PI/1.5);
                const tween3 = new TWEEN.Tween(gltf.scene.position);
                tween3.to({ x: 100, y: 50, z: 0 }, 5000).start()
            });

            //创建一段缩放的动画
            const tween2 = new TWEEN.Tween(gltf.scene.scale);
            tween2.to({ x: 0.01, y: 0.01, z: 0.01 }, 10000);

            tween.start();
            tween2.start();

            // ---------确保模型的每个网格都启用投射阴影-----------
            gltf.scene.traverse((child) => {
                if (child instanceof THREE.Mesh) {
                    child.castShadow = true; // 启用投射阴影
                }
            });


        })



        renderer.setSize(box.clientWidth, box.clientHeight)
        box.appendChild(renderer.domElement)
        new OrbitControls(camera, renderer.domElement)

        animate()
        function animate() {
            TWEEN.update();
            requestAnimationFrame(animate)
            renderer.render(scene, camera)
        }

    </script>

</body>

</html>